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-rw-r--r--nptl/sysdeps/pthread/pthread_once.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/nptl/sysdeps/pthread/pthread_once.c b/nptl/sysdeps/pthread/pthread_once.c
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+++ b/nptl/sysdeps/pthread/pthread_once.c
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+/* Copyright (C) 2002 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "pthreadP.h"
+#include <lowlevellock.h>
+
+
+
+static lll_lock_t once_lock = LLL_LOCK_INITIALIZER;
+
+
+int
+__pthread_once (once_control, init_routine)
+     pthread_once_t *once_control;
+     void (*init_routine) (void);
+{
+  /* XXX Depending on whether the LOCK_IN_ONCE_T is defined use a
+     global lock variable or one which is part of the pthread_once_t
+     object.  */
+  if (*once_control == PTHREAD_ONCE_INIT)
+    {
+      lll_lock (once_lock);
+
+      /* XXX This implementation is not complete.  It doesn't take
+	 cancelation and fork into account.  */
+      if (*once_control == PTHREAD_ONCE_INIT)
+	{
+	  init_routine ();
+
+	  *once_control = !PTHREAD_ONCE_INIT;
+	}
+
+      lll_unlock (once_lock);
+    }
+
+  return 0;
+}
+strong_alias (__pthread_once, pthread_once)